1. Technical Field of the Invention
This invention generally relates to a coin mechanism for use in a vending machine, and more particularly, to a change returning device employed in the coin mechanism.
2. Description of the Prior Art
Coin mechanisms having a change returning device are well known in the art. Such a conventional coin mechanism is schematically illustrated in FIG. 1.
With reference to FIG. 1, one conventional coin mechanism 10' includes housing 11 which contains a deposited coin-like object Judging device 13, a plurality of, for example, four coin stacking cylindrical tubes 14 and an extra coin stacking cylindrical tube 15 therewithin. The judging device 13 is linked to a coin conducting port 12 which is provided at a top end portion of the housing 11. The coin stacking tubes 14 are located at a position below the judging device 13, and are linked to the judging device 13 through a sorting device (not shown). A plurality of, for example, four kinds of coins 30a, 30b, 30c and 30d are stacked within the four coin stacking tubes 14, respectively. The coin stacking tubes 14 are adjacent to each other, and extend along the longitudinal axis of the housing 11. The extra coin stacking tube 15 is adjacent to one coin stacking tube 14 which is located at an outermost side, and also extends along the longitudinal axis of the housing 11. One kind of coins, for example, coins 30a are preliminarily and supplementarily stacked within the extra tube 15. Furthermore, an inner diameter of each of the cylindrical tubes 14 and 15 is designed to be slightly greater than a diameter of the corresponding coins 30a, 30b, 30c and 30d.
Each of the coin stacking tubes 14 is provided with a change returning device (not shown) at a position immediately therebelow. The extra coin stacking tube 15 is also provided with a change returning device 16 (hereafter, returning device 16) which is described in detail below with reference to FIGS. 2 and 3.
With reference to FIGS. 2 and 3, the returning device 16 is located at a position immediately below a lower end of extra tube 15. For purposes of explanation only, in FIGS. 2 and 3, the left side will be referred to as the front or forward side and the right side will be referred to as the rear or rearward side. The returning device 16 includes a ring-shaped coin ejector 161 and a coin catching plate member 162 which is located at a position below the coin ejector 161. The coin catching plate member 162 comprises a sloped surface 162a and a vertical groove 162b that is continuous with a lower edge of the sloped surface 162a. The sloped surface 162a is inclined from the rear to the front. The degree or amount of angular incline of the sloped surface 162a is designed such that a coin 30a can smoothly slide along the sloped surface 162a. A bottom surface 162c of the vertical groove 62b declines (from the right to the left in FIG. 1), and an inner width of the groove 162b is designed to be slightly greater than the thickness of the coin 30a. Furthermore, a part of the coin catching plate member 162 forms a receiving portion 162d which is capable of receiving a front peripheral region of the ring-shaped coin ejector 161 and a part of an outer peripheral region of the lowest coin 30a stacked within the extra tube 15. A projection 161a is formed at an inner lower peripheral surface of a rear region of the ring-shaped coin ejector 161 diametrically opposite to the receiving portion 162d of the coin catching plate member 162. A projecting end of the projection 161a is terminated such that it does not project beyond a center point of the ring-shaped coin ejector 161. Furthermore, an inner diameter of the coin ejector 161 is designed to be slightly greater than the diameter of the coin 30a.
The coin ejector 161 is operatively connected to a driving device (not shown), and reciprocatingly moves forwardly and rearwardly (to the left and the right in FIGS. 2 and 3) by virtue of operation of the driving device. That is, in FIG. 1, the coin ejector 161 reciprocatingly moves along a line perpendicular to a drawing sheet. FIG. 2 illustrates one situation where the coin ejector 161 is positioned at the forwardmost point of the reciprocating movement thereof. In this situation, the coin ejector 161 is located at a position just below a lower end of extra tube 15, so that a center point of the ring-shaped coin ejector 161 is essentially aligned with the longitudinal axis of the extra tube 15. Therefore, the lowest coin 30a stacked within the extra tube 15 is contained within the ring-shaped coin ejector 161, and is stably received by the receiving portion 162d of the coin catching plate member 162 and the projection 161a of the ring-shaped coin ejector 161.
FIG. 3 illustrates the other situation where the coin ejector 161 is positioned at the rearmost point of the reciprocating movement thereof. In this situation, the coin ejector 161 is located at a position where the center point of the ring-shaped coin ejector 161 is rearwardly offset from the longitudinal axis of the extra tube 15 by a maximum distance. However, the front peripheral region of the ring-shaped coin ejector 161 is still received on the receiving portion 162d of the coin catching plate member 162 and a front peripheral end of the ring-shaped coin ejector 161 is forwardly offset from the longitudinal axis of the extra tube 15 by a slight amount. Therefore, the second lowest coin 30a stacked within the extra tube 15 is received by the projection 161a of the ring-shaped coin ejector 161.
In a stroke where the coin ejector 161 moves from the forwardmost point as depicted in FIG. 2 to the rearmost point as depicted in FIG. 3, the coin 30a contained within the ring-shaped coin ejector 161 falls therefrom just after a time when an inner surface of the front peripheral region of the ring-shaped coin ejector 161 leaves from the receiving portion 162d of the coin catching plate member 162.
In operation, a coin-like object (not shown) deposited through a coin slot (not shown) of a vending machine is conducted into the judging device 13 via the coin conducting port 12, and is thereby Judged whether it is a real coin and what kind of coin it is. The coin-like object judged as one of the kind of real coins is sortingly distributed to the corresponding coin stacking tube 14 by the sorting device (not shown) in response to demand.
The coins stacked within each of the stacking tubes 14 are temporarily stored there, and are ejected therefrom one by one beginning with the lowest stacked coin by virtue of operation of the change returning device (not shown) in response to demand. The coin ejected from the stacking tubes 14 falls to a change receiving window (not shown) through a funnel-shaped duct member (not shown).
When the number of the coins 30a stacked within the corresponding tube 14 decreases to a first predetermined value, an operation of ejecting the coins 30a from the corresponding tube 14 is terminated, and simultaneously, an operation of ejecting the coins 30a from the extra tube 15 is initiated. During the operation of ejecting the coins 30a from the extra tube 15, the coins 30a are distributed from the judging device 13 to the corresponding tubes 14, and therefore, the number of the coins 30a stacked within the corresponding tube 14 increases from the first predetermined value. When the number of the coins 30a stacked within the corresponding tube 14 increases to a second predetermined value which is significantly larger than the first predetermined value, the operation of ejecting the coins 30a from the extra tube 15 is terminated, and simultaneously, the operation of ejecting the coins 30a from the tube 14 is reinitiated. Thus, the operation of ejecting the coins 30a from the corresponding tubes 14 and the extra tube 15 is selectively carried out in response to the number of the coins 30a stacked within the corresponding tubes 14.
The operation of ejecting the coins 30a from the extra tube 15 is described with reference to FIGS. 2 and 3. As described above, in the stroke where the coin ejector 161 moves from the forwardmost point as depicted in FIG. 2 to the rearmost point as depicted in FIG. 3, the coin 30a contained within the ring-shaped coin ejector 161 falls therefrom Just after the time when the inner surface of the front peripheral region of the ring-shaped coin ejector 161 leaves from the receiving portion 162d of the coin catching plate member 162.
The coin 30a falling from the coin ejector 161 is caught by the sloped surface 162a of the coin catching plate member 162, and slides along the sloped surface 162a with either the head or tail surface of the coin 30a in contact with an upper surface of the sloped surface 162a as illustrated in FIG. 3. The coin 30a sliding along the sloped surface 162a is received within the vertical groove 162b by pivoting about a lower peripheral portion thereof in one direction (in the counter clockwise direction in FIG. 3). Once the coin 30a is received within the vertical groove 162b, the coin 30a rolls along the inclined bottom surface 162c of the groove 162b as illustrated in FIG. 1. Finally, the coin 30a rolling along the inclined bottom surface 162c of the groove 162b leaves coin mechanism 10' from a lower end of the groove 162b, and falls to the change receiving window (not shown) through the funnel-shaped duct member (not shown).
In general, it is required to smoothly conduct the coin 30a sliding along the sloped surface 162a into the vertical groove 162b in order to avoid a jam of the coin 30a at the sloped surface 162a and/or the vertical groove 162b. One solution to avoiding this jam or blockage is to increase the amount of angular incline of the sloped surface 162a, so that the coin 30a sliding along the sloped surface 162a is smoothly conducted into the vertical groove 162b.
However, in a limited space, as the inclined angular amount of the sloped surface 162a is increased, a longitudinal length of the extra tube 15 is decreased. As a result, the number of coins 30a preliminarily and supplementarily stacked within the extra tube 15 may not total the preferred value which prevents the vending machine from frequently running out of coins for returning change. Thus, the vending machine may run out of coins more frequently and may not be able to effectively operate.